Fuse



Nay. 19, 1940. H; A, TRIPLETT 2,221,958

FUSE

Filed July 22, 1937 5 Sheets-Sheet 2 Nov. 19, 1940. H. A. TRIPLETT FUSE 5 Sheets-Sheet 5 Filed July 22, 1937 Nm mm J m Q l kk 5 Sheets-Shet 4 Nov. 19, 1940. H. A. TRIPLETT FUSE Filed July 22, 19s? Nov. 19, 1940. A TRlPLETT 2,221,958

FUSE

Filed July 22, 1937 5 Sheets-Sheet 5 .ZZIqdfi .7

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v w /ZA w ;& 9.6 Q /20 A 722 A A A Patented Nov. 19, 1940 UNITED STATES FUSE Hugh A. Triplett, Wilmette, 111., assignor to Schweitzer & Conard, Inc., Chicago, 111., a corporation of Delaware Application July 22, 1937., Serial No. 154,941

14 Claims,

My invention relates, generally, to circuit interrupters and it has particular relation to mounting devices for fuse housings and fuse links, such as are disclosed in my copending application, Serial No. 144,789, filed May 26, 1937, and assigned to the assignee of this application, which are particularly well suited for connection in the low voltage high current circuit of a distribution 'transformer, although they are not limited for use in this particular application.

In my copending application I have disclosed a fuse link that comprises a fusible element interconnecting a pair of terminals to each of 15 which is connected a flexible lead for the purpose of. connecting the link in a circuit. The link, in one embodiment, is arranged for mounting in a tubular fuse housing that vents at each end when the link blows. The flexible leads extend out of the ends of the housing and are clamped around tubular terminals at these ends which not only provide circuit connections thereto but also provide for venting the fuse housing.

Since the fuse housing vents in opposite directions on blowing of the fuse link, it is unneces sary to provide a mounting that is capable of withstanding relatively great stress for the reason that the reaction forces are neutralized. This is particularly advantageous when the stresses set up under some short circuit conditions are considered. In order to obtain a selective action with respect to fuse devices connected in the high voltage low current circuit of the distribution transformer, it is necessary to proare capable of operating continuously on flow of current close to the minimum fusing current without blowing and without causing any change in the operating characteristics of the fuse devices that would alter their time-current characteristics. Under such operating conditions the temperature of thefusible element of the fuse device should be relatively low so that the adjacent housing and supporting structure will not be injured by excessive heat. For this purpose, according to my copending application, I have provided a composite fusible element in a fuse link that comprises-a low melting point core and a high melting point sheath therefor. For example, the core may be composed of tin and the sheath may be composed of silver. By combining' the operating characteristics of two such metals it is possible to provide a fuse link that is capable of operating continuously at a relatively low temperature close to its minimum fusing current and at the same time its time-current characteristic remains substantially unchanged.

The object of this invention, generally stated, is to provide mountings for certain of the fuse housings and links disclosed in my copending ap iii) vide fuse devices in the secondary circuit that plication that will be simple and eflicient in op eration and which may be readily and economically manufactured and installed.

An object of my invention is to detachably mount a fuse housing that vents both ends in such manner that venting thereof will not be interfered with and at the same time provides for connecting the device in an electric circuit.

A further object of my invention is to provide a fuse construction which can be refused without hazard to the lineman in which contact resistance and losses between the replaceable fuse link and container or housing therefor, between container and mounting therefor, and between mounting and line conductors are reduced to a minimum.

Another object of my invention is to mount a signal lamp in a novel manner to indicate that a fuse device of the foregoing type has operated.

A further object of my invention is to provide novel means for clamping and unclamping a tubular terminal of a fuse housing.

A still further object of my invention is to electrically interconnect by a renewable fuse link a pair of line conductors that extend in opposite directions from an insulator mechanically interconnecting them.

Another object of my invention is to provide for testing an overhead electric circuit in which a fuse link has blown to determine if it is safe to replace the blown fuse link.

Still another object of my invention is to' provide for mounting a renewable fuse link in a housing intended to be closed at one end and open at the other when the fuse link blows.

Another object of my invention is to provide a novel means for indicating that a fuse link has blown.

Other objects of my invention will, in part, be obvious and in part appear hereinafter.

Accordingly, my invention is disclosed in the embodiments thereof shownin the accompanying drawings and it comprises the features of construction, combination of elements and ar rangement of parts which will be exemplified in the description hereinafter set forth and the scope of the application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of my invention, reference may be had to the following detailed description taken in connection with the accompanying drawings in which:

Figure 1 is a. view, partly in side elevation and partly in section, of one embodiment of my novel mounting structure for fuse housings;

Figure 2 is a view in front elevation of a shunt blade that may be employed in connection with the mounting shown in Figure 1;

Figure 3 is a view, in front elevation, of the mounting device shown in Figure 1, with the shunt blade in position;

Figure 4 illustrates diagrammatically the cir-' cuit connections that may be employed in practicing my invention;

Figure 5 is a view, in front elevation, showing how two of the fuse housing mountings shown in Figure 1 together with the signal lamps therefor may be positioned on a power line pole or the like and connected in the circuit;

Figure 6 is a view, in front elevation, showing how the single mounting shown in Figure 1 may be positioned on a pole and interconnected in a single circuit;

Figure 7 is a view, in side elevation, of another embodiment of my invention in which a pair of line conductors is interconnected mechanically by an insulator and a mounting is provided for receiving a fuse link to interconnect them electrically;

Figure 8 is a view, in bottom plan, of the con-- struction shown in Figure 7;

Figure 9 is a detail sectional view taken along the line 9-9 of Figure 7;

Figure 10 is a longitudinal sectional view of the fuse link housing shown in Figure 7;

Figure 11 is a view, in front elevation, of a device for receiving a fuse link and adapted to check a circuit to determine whether or not it is safe to re-fuse the same;

Figure 12 is a view, in end elevation, of the device shown in Figure 11;

Figure 13 is a detail sectional view taken along the line I3|3 of Figure 11;

Figure 14 is a longitudinal sectional view of a fuse housing arranged to be closed at one end and adapted to receive a fuse link having a flexible lead at each end;

Figure 15 is a view, in bottom plan, of the housing shown in Figure 14; and

Figure 16 is a fragmentary longitudinal sectional view of the housing shown in Figure 14 illustrating how a universal fuse link having only one flexible lead canbe mounted therein instead of the fuse link with a flexible lead at each end.

Referring now particularly to Figures 1 and 3 of the drawings, it will be observed that the reference character 20 indicates a fragmentary portion of a power line pole or other suitable support for carrying a generally U-shaped bracket 2| on which is mounted a fuse housing mounting, shown generally at 22. The mounting 22 is arranged to support a fuse housing, shown generally at 23, and to provide electrical connection thereto. The bracket 2| is provided with feet 24 that are suitably apertured for receiving lag screws 25, or the like, for mounting the apparatus on the pole 20.

The mounting 22 comprises a base 26, formed of suitable insulating material such as ebony asbestos, and it is provided with centrally located countersunk apertures for receiving bolts 21 from the front face that are threaded into the bracket 2|. By providing for mounting the base 26 midway its ends on the bracket 2|, the ends thereof are left free for terminal clamps for 1 receiving the fuse housing 23 as will be presently apparent.

The fuse housing 23, which is adapted to receive a replaceable fuse link, is fully described in my copending application, hereinbefore referred to, and, therefore, only a brief description of it will be set forth herein. Generally, itcomprises a fuse tube 3|] of insulating material having ferrules 3| threaded on its ends. The ferrules 3| are provided with tubular extensions 32 to permit electrical connection to the device and at the same time provide for venting the interior of the tube 30. The ends of the extensions 32 may be closed by plugs 33, such as corks, that are readily expellable on the generation of pressure within the fuse tube caused by blowing of the fuse link therein. For mounting the fuse housing 23 which vents at both ends, it is necessary to provide suitable clamps at its ends which will not interfere with the venting on blowing of the fuse link.

With a view to mounting the fuse housing 23 in this manner, terminal clamps 34 are provided at the ends of the base 26. The terminal clamps 34 are generally J-shaped having a relatively long arm 35 adjacent the base 26 and a relatively short arm 36 spaced therefrom between which the extensions 32 of the ferrules 3| are positioned. The terminal clamps 34 are secured to the ends of the base 26 by bolts 31 and 36 that are positioned in suitable counterbored apertures, as shown in Figure i. It will be observed that the bolts 31 and 38 are threaded into suitably tapped apertures in the relatively long arms 35.

With a view to removably clamping the extensions 32 of the ferrules 3| in position, each of the long arms 35 of the terminal clamps 34 is provided with a groove 4| along its inner surface that connects with an aperture 42 that extends through the lower end thereof. A clamp bolt 43 is slidably mounted in each of the grooves 4| and apertures 42 and at its upper end it is provided with a headed end 44 that is formed by flattening this end and then turning the same over, as illustrated. Wing nuts 45 threaded on the lower ends of-the clamp bolts 43 serve to hold the headed ends 44 of the clamp bolts 43 in clamping engagement with the extensions 32.

It is desirable that the rotation of the wing nuts 45 cause a positive movement of the clamp bolts 43 toward and away from the clamping position. For this purpose each of the wing nuts 45 is provided with an integrally formed boss-46 having a circumferential groove 41 therein. The boss 46 extends into a suitable enlarged aperture in the underside of each of the terminal clamps 34 and, as shown, these enlarged aper tures are coaxial with the apertures 42. Pins 46, only one of which is shown, extend through the lower ends of the terminal clamps 34 and interfit with the grooves 41 to prevent axial movement of the wing nuts 45. Since longitudinal movement of the wing nuts 45 is prevented, rotation thereof will cause a positive movement of the clamp bolts 43 toward and away from the clamping depending upon the direction of rotation of the wing nuts 45.

The electrical connection with the terminal clamps 34 by line conductors is provided by integrallyformed sockets 49 into which set screws 50 are threaded. Obviously, any other suitable clamping means may be provided for securing the line conductors to the terminal clamps 34.

With a view to providing further indication of whether or not the fuse link in the fuse housing 23 has blown, a lamp socket 53 is mounted in the lower leg of the U-shaped bracket 2| and it has positioned therein an indicating lamp 54. The indicating lamp 54 may be of the incandescent type or it may be of the gas filled type or glow discharge type as may be desired. Conductors 55 are provided for connecting the lamp 54 in the lamp socket 53 across the terminals of the fuse housing 23. As shown the conductors 55 are provided with suitable terminals and, by means of screws 56, only one of which is shown, they are connected to the lower bolts 38 that hold the terminal clamps 34 to the ends of the base 26.

As long as the fuse link in the fuse housing 23 remains intact the lamp 54 is short circuited. However, as soon as the fuse link blows, and some load remains connected across the line, the lamp 54 will be lighted, thereby indicating that the fuse link has blownand should be replaced.

In order to protect the lamp 54 a suitable metallic cap 51 may be provided thereover and secured, as shown, to the underside of the bracket 2|. The cap 51 is provided with suitable apertures to permit the light rays from the lamp 54 to be visible from the ground to the line inspector. Ordinarily the lamp 54 will be provided with a colored bulb, such as red, so that on becoming lighted it will be readily visible.

7 In some cases it may be desirable to remove the fuse housing 23 for testing or other purposes and at the same time to provide for continuity of service on the line. For this purpose a shunt blade 58, Figure 2, is provided having a handle 59 formed of molded insulation at one end. The blade 58 is provided with slotted apertures 50 for interfitting with bolts 6| that are threaded into the lower ends of the relatively short arms 36 of the terminal clamps 34. Washers 52 are provided on the bolts 6i together with coil compression springs 63. After the shunt blade 58 is in position, the bolts 5| may be tightened to resiliently hold it in position between the washers 8| and the short arms 38 of the terminal clamps 34. In this manner the application and removal of the shunt blade 58 is entirely independent of the clamp bolts 43 which serve to removably clamp the fuse housing 28 in position. Once the shunt blade 58 has been clamped in position the fuse housing 23 may be removed without interruption of the circuit.

Figure 6 of the drawings shows the manner in which the fuse housing mounting 22, shown in Figures 1 and 3 of the drawings, is employed. As there shown, line conductors A are dead-ended at the pole 20 by any suitable means. For example, the U-shaped brackets 86 may be employed having spool type insulators 61 carried thereby. The ends of the conductors A may be looped around the insulators 51 and secured, as shown. Jumper connections 58 are provided for interconnecting the line conductors A and the sockets 49'integrally formed with the terminal clamps 34.

In Figure 5 of the drawings I have illustrated the manner in which two of the fuse mountings 22 may be employed in connection with a single phase three-wire circuit comprising a neutral conductor N and conductors A and B. The line conductors N, A and B may be dead-ended at thepole 20 on suitable insulators, such as the spool type insulators, that are carried on suitable mounting brackets II. Two mountings 22 are mounted at opposite ends of a suitable base 12, formed of insulating material, that is in turn mounted by a suitable bracket on the pole 28. The jumper connections 58-are provided to interconnect the line conductors A and B with the sockets 49 in their respective terminal clamps 34. These are, in turn, interconnected by the fuse links in the fuse housings 23. A single jumper connector 13 serves to interconnect the line conductors N. Since this is the neutral conductor, it is unnecessary to fuse it.

In Figure 4 of the drawings, the circuit connections that may be employed for practicing the present invention are shown with special reference to a three-wire single phase distribution circuit. The line conductors may be the conductors A, B, and N, shown in Figure 5 and previously described. For energizing these conductors a transformer, shown generally at 15, is provided having a primary winding 16 for connection to a suitable source of single phase alternating current, such as a 60-cycle source. The transformer is provided with a. secondary winding 11 the terminals 18 and 19 of which are connected to the line conductors A and B respectively through fuse links 88 and 8!. The fuse links 80 and 8! may be and preferably are of the type shown in my copending application, hereinbefore referred to, and are contain-ed in the fuse housing 23, shown in Figures 1 and 3 of the drawings and described hereinbefore. The secondary winding 11 is provided with a mid-tap 82 for direct connection to the neutral conductor N. The distribution circuit may be arranged for operation at the standard voltage of 230 volts between the conductors A and B and 115 volts between either of these conductors and the neutral conductor N. Typical load devices, such as the motors 83 and 84, may be connected between the conductors A and B and the neutral conductor N, as shown. 0n the flow. of fault current on either of the conductors A or B, the corresponding fuse link 80 or 8| will blow. Assuming that some load device, such as either of the load devices as 83' or 84 remains connected to the circuit, then the indicating lamp 85 or 86 will be lighted as soon as the corresponding fuse link 88 or 8i blows. The indicating lamps 85 and 86 may be of the type shown at 54 in Figures 1 and 3 of the drawings and described hereinbefore. The lighting of one or both of these lamps indicates that the fuse link corresponding thereto has blown and should be replaced in order to restore service.

In some installations it may be undesirable to dead-end the line conductors at a pole. It may be preferable to dead-end them intermediate the poles. For such an installation, the construction shown in Figures 7, 8, 9, and 10 may be employed with advantage. ductors A are dead-ended by means of a single insulator 89 through which they are looped in suitable apertures at right angles to each other, the ends being clamped by suitable clamps 98. The line conductors A are thus mechanically interconnected but, because of the insulator 89, they are insulated from each other;

The conductors A may be electrically interconnected by a replaceable fuse link 9| that is provided with flexible leads 92 at its ends. The fpse link 9| may be of the type described in detail in my copending application, hereinbefore referred to. The ends of the flexible leads 92 may be secured, as by clamps 93, to support members 94, in the form of copper rods, the ends of which As there shown, the line conare off-set so that they will be parallel with the undersides of the line conductors A for clamping thereto by-suitable clamps 95.

With a view to protecting the fuse link 9| from the weather, a fuse housing 95 is provided. As shown, longitudinally extending apertures 91 are provided near the top surface of the housing 95 and they are of such diameter as to provide a snug fit with the opposing ends of the support members 94 which are secured therein by transverse pins 98. As shown in Figure 9 of the drawings, the pins 98 are disposed in suitable apertures, the ends of which are counterbored for receiving a suitable plastic material 99 for filling the same.

The fuse link 9i is mounted in a suitable longitudinally extending aperture I00 adjacent the lower surface of the housing 96 which terminates in enlarged apertures IOI. This construction with the enlarged apertures IN is provided to insure that the gases generated on blowing of the fuse link 9I will be free to escape from the housing 96 in opposite directions with one result being that the radial pressure components on the walls of the aperture I00 will be minimized. There will then be substantially no reaction between the housing 96 and the support members 94 therefor.

If, after blowing of a fuse, a fault still exists on the circuit in which the fuse construction and mounting shown in Figures 7, 8, 9, and 10 is employed, it is dangerous for the lineman to replace the blown fuse link. It will be obvious, under such conditions, that the new fuse link will immediately blow and, since the lineman is required to be in close proximity to the housing 95 for replacing the fuse link, it is possible that he may be severely burned.

With a view to obviating this dangerous con dition the circuit checking apparatus shown in Figures 11, 12 and 13 may be employed. By the use of this apparatus, it is possible to determine whether the fault condition still persists. This apparatus comprises the device shown generally at I04 which includes a tubular insulating member I05 formed of a material such as Bakelite. Intermediate its endsa fitting I05 is provided for receiving the threaded end of a handle I0I that is formed of a suitable insulating material such as wood. The tube I05 is arranged for receiving a fuse link I08 therein having flexible leads I09 at its ends. The link I08 may be similar to the link 9I shown in Figures 7 and 8 of the drawings and described hereinbefore.

As shown, the fuse link I 08 is positioned inside of the tube I05 midway its ends and the flexible leads I09 are positioned between spring clips H0 and III that form extensions of a generally U- shaped contact prong H2. The contact prong H2 is formed of conducting material such as phosphor bronze and the upper portion is held in position by a suitable rivet H3 and spacers II 4. Rivets II5 serve to hold the contact prongs II2 to the ends of the tube I05. The end 0 of the spring clip I I0 is turned upward a slight amount in order to facilitate the positioning of the flexible lead I09 between it and the spring clip III.

Before replacing the fuse link, suchas the fuse link 9| shown in Figures '7 and 8, the lineman places a fuse link, such as the fuse link I00, in the tube I05 and then by grasing the handle I0'I moves the contact prongs H2 into contact engagement with the support members 94. If the fault still persists, the fuse link I00 will be immediately blown but, since it is spaced some distance away from the lineman, he will not be harmed. The circuit can then be inspected to locate the fault and to remove the same before the circuit is re-fused.

There are some installations in which it is desirable to provide for out-of-doors mounting of a fuse link having a flexible lead at each end in a housing, one end of which is adapted to remain closed when the fuse link blows. Such a fuse housing is shown generally at H9 in Figure 1-1 of the drawings. This housing I I9 is arranged I for mounting in a vertical position and is adapted to receive a fuse link I20 having flexible leads I2I and I22 at its ends. The fuse link-I20 is of the type that is shown and described in my copending application, hereinbefore referred to.

The housing II9 comprises an outer tube I24, formed of a material such as Bakelite," and an inner tube or liner I25 formed of a material such as fiber that is capable of evolving an are extinguishing medium on blowing of the fuse link I20.

At its upper end the housing H9 is provided with an upper ferrule I20 to which may be connected a terminal fitting I2I for receiving a line.

conductor. A pin I20 extends transversely through the shank of the'terminalfitting that projects into the ferrule I 26 for securing it in position.

At its upper end the upper ferrule I29 is provided with a threaded reduced end portion I29 to form a shoulder I30 for receiving the end of the flexible lead I2I. The reduced end portion I29 is provided with a longitudinally extending aperture I9I that constitutes an extension of the bore of the fiber liner I25 and it is provided with a slotted opening I32 through which the flexible lead I2I may be positioned to permit its being placed around the reduced end portion I29 and on the shoulder I 30. A cap I33 having a shoulder I34 is threaded on the reduced end portion I29 for closing the upper end of the housing H9 and securing the flexible lead I2I in position between the shoulders I30 and I34. The cap I33 is provided with adepending flange I35 that overlaps the shoulder I30. A pin I35, extending transversely through the upper ferrule I26 and a portion of the outer tube I24, serves to securely hold the upper ferrule I26 on the housing II9. Since the cap I33 is threaded on the ferrule I25, the upper end of the housing H9 is closed and ordinarily will remain closed on blowing of the fuse link I20.

The lower end of the housing H9 is arranged to be open so that free venting downwardly is permitted on blowing of the fuse link I20. At this lower end a combined lower ferrule and housing I39 is provided having a depending skirt I40. A pin I4I extending transversely through the ferrule I39 and a portion of the outer tube I24 serves to secure the former to the latter. A terminal socket I42 is integrally formed with the skirt I40 and the flexible lead I22 is securely clamped therein by a set screw I43. Connection to the lower ferrule and housing I39 is provided by a terminal fitting I44 the shank of which projects into the skirt I40 and is secured therein by a pin I45.

It is desirable to provide an indication that the fuse link I20 has blown. For this purpose an indicator arm I40 having an integrally formed boss I41 is located within the skirt I40 and is rotatably mounted on a transverse pin I48 that extends between the depending sides thereof. At its outer end the indicator arm I46 is provided with a target I49 that is circular in shape and has shallow sockets I50 on opposite sides thereof for receiving indicator discs I5I.

use either a flashlight or a spot light to pick up the discs I5I as will be readily understood.

, A mechanical connection between the flexible lead I22 and the indicator arm I46 is provided by a pawl I52 that is mounted for rotation on a pin I53 which extends transversely through the skirt I40. The outer end I54 of the pawl I52 is grooved to receive the flexible lead I22. The pawl I52 is provided with a tooth I55 for interfitting with a notch I56 in the boss I41.

When the fuse link I20 has been placed in the housing I29, as shown in Figure 14 of the drawings, and the flexible lead I22 drawn up tightly and secured by'the set screw I43, the indicator arm I46 will be held in the position shown and the targetv I49 with the discs I5I therein will be concealed from view by the skirt I40. As soon as the fuse link I20 blows, the pawl I52 is no longer restrained and the indicating arm I46 is free to rotate downwardly carrying with it the target I49. Casual inspection of the device will reveal that the fuse link I20 has blown since the discs I5I of the target I49 will then be clearly visible.

In order to apply a spring tension to the fuse link I20 and to insure that the pawl I52 will be moved when the fuse link blows, a coil compression spring I51 may be interposed between the back side of the pawl I52 and the adjacent inner surface of the skirt I40. A boss I58, formed with the pawl I52, serves to center the spring I51.

As shown in Figure 16 of the drawings, the upper ferrule I26 and the cap I33 are also arranged to receive a universal fuse link I20, the construction of which is similar to that of the fuse link I20 and which is described in detail in my copending application hereinbefore referred to. Generally, the difference between the fuse links I20 and I20 resides in the omission of the upper flexible lead I2I from the former and the provision of a button terminal I60 on the latter. The upper end of the insulating sleeve of the fuse link I20 iscrimped or otherwise secured to a suitable terminal onto which the button terminal I60 may be threaded, as described in my said copending application.

It will be obserbed that the radially extending flange of the button terminal I60 is positioned between the upper face I6I of the end portion I29 and the under face I62 of the cap I33. The space between the shoulders I30 and I34 is suilicient to permit the cap I33 to be screwed tightly onto the button terminal I60.

In this manner it is possible to employ the same upper terminal construction for the housing II9 to receive either type of fuse link without requiring any change to adapt it for one or the other. Consequently, the same housing II9 can be used for receiving many of the replaceable fuse links that are available in the open market.

' Since certain changes may be made in the foregoing constructions and different embodiments of the invention may be made without departing from the scope thereof, it is intended that all matter shown on the accompanying drawings are described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. A circuit interrupting means comprising, in combination, a fuse housing having metal ferrules adjacent its ends adapted to be interconnected by a renewable fuse link therein, said' ferrules having openings for venting said housing at both ends on blowing of said fuse link, a terminal clamp removably attached to each ferrule in such position as not to interfere with the venting of said housing from both ends, conductor receiving means on each terminal clamp, a shunt member, and means for detachably clamping said shunt member to each terminal clamp for inter.- connecting the same.

2. Circuit interrupting means comprising, in combination, an insulating base; a pair of clamp jaws mounted in parallel spaced apart relation on said base each comprising a generally J- shaped metal clamp member having a groove extending along substantially the entire length of the inner surface of its longer arm and an aperture aligned therewith and extending through its base, clamp means having a headed end slidably mounted in said groove and aperture, and a conductor receiving socket; and a tubular fuse housing having metal ferrules adjacent its ends adapted to be interconnected by a renewable fuse link therein, said ferrules having openings for axially venting said housing at both ends on blowing of said fuse link and arranged and adapted to be clamped between said headed ends of said clamp means and the shorter arms of said J-shaped clamp members in such position as not to interfere with the axial venting of said housing from both ends.

3. A terminal connecter for detachably receiving a tubular terminal of a fuse housing adapted for axial venting at both ends on blowing of a fuse link therein comprising, in combination, a generally J-shaped metal clamp member having a groove extending along substantially the entire length of the inner surface of its longer arm and an aperture aligned therewith and extending through its base, a clamp rod having a headed end slidably mounted in said groove and aperture, means for adjustably positioning said clamp rod in said groove for clamping said tubular terminal between its headed end and the shorter arm of said clamp member with the bore thereof free to vent outwardly, and means for securing a line conductor to said clamp member.

4. A terminal connecter for detachably receiving a tubular terminal of a fuse housing adapted for axial venting at both ends on blowing of a fuse link therein comprising, in combination, a generally J-shaped metal clamp member having a groove extending along substantially the entire length of theinner surface of its longer arm and an aperture aligned therewith and extending through its base, a clamp rod headed at one end and threaded at the other slidably mounted in said groove and aperture, a nut on said threaded end of said rod, means rotatably mounting said nut on said clamp member and preventing relative longitudinal movement whereby said clamp rod is moved in said groove and aperture on rotation of said nut in either direction to clamp and unclamp said tubular terminal between said headedend and the shorter arm of said clamp member with the bore thereof free to vent outwardly, a socket portion for receiving a line conductor integrally formed with saidclamp member, and means for securing said line conductor in said socket portion.

5. For combination with a. pair of line conductors one constituting a continuation of the other and disposed in insulated relation; a pair of support members formed of conducting material, adapted to be connected at one end to said line conductors and extending toward each other in spaced apart relation at the other end; a fuse housing having an aperture extending inwardly from each end for receiving the spaced apart ends of said support members therein and an aperture extending longitudinally therethrough, a fuse link in said longitudinally extending aperture having flexible leads extending out of the ends thereof, and means for securing said flexible leads to said support members, thereby electrically interconnecting said line conductors.

6. For combination with a pair of line conductors extending along substantially a straight line and insulated from each other; a pair of substantially rigid support members formed of conducting material, adapted to be clamped at one end to said line conductors and extending toward each other with the ends spaced apart; a fuse housing having an aperture extending inwardly from each end for receiving therein said spaced apart ends of said support members and an aperture extending longitudinally therethrough, a fuse link in said longitudinally extending aperture having flexible leads extending out of its ends, and means for clamping said flexible leads to said support members, thereby electrically interconnecting said line conductors.

7. In an electric distribution system, in combination, an insulator, a pair of line conductors having the adjacent ends looped over said insulator thereby being electrically insulated from each other and extending in opposite directions therefrom; a pair of rod-like conductors having offset end portions, means clamping said end portions to the under sides of said line conductors with the other end portions extending substantially parallel thereto and the ends thereof spaced apart, a block of insulation having an aperture extending longitudinally inwardly from each end for receiving therein said spaced apart end portions of said rod-like conductors and an aperture extending longitudinally therethrough having enlarged end portions, means securing said rod-like conductors in said block of insulation, a fuse link in said longitudinally extending aperture having flexible leads extending out of its ends, and means clamping said flexible leads to the under sides of said rod-like conductors, thereby electrically interconnecting said line conductors.

8. A fuse housing for mounting out-of-doors in a vertical position and adapted to receive a renewable fuse link having flexible leads at its ends comprising, in combination, a fuse tube, a terminal at the upper end of said fuse tube adapted to receive one flexible lead of said fuse link, means closing the upper end of said fuse tube and capable of keeping the same closed on blowing of said fuse link, a closure at the lower end of said fuse tube opening downwardly, means on said closure for receiving the other flexible lead of said fuse link, and indicating means within said closure including a target controlled by said fuse link, said target dropping below said closure on blowing of said fuse link.

9. A fuse housing for mounting out-of-doors in a vertical position and adapted to receive a renewable fuse link having flexible ler ds at its ends comprising, in combination, a fuse tube, a terminal at the upper end of said fuse tubeadapted to receive one flexible lead of said fuse link, means closing the upper end of said fuse tube and capable of keeping the same closed on blowing of said fuse link, a metal housing secured to the lower end of said fuse tube having a flared out portion opening downwardly, means for connecting the other flexible lead of said fuse link to said hous- 2,221,aae

ing, a target rotatably mounted in said housing. a pawl rotatably mounted in said housing and cooperating with said other flexible lead and said target to restrain the latter as long as said fuse link remains intact, and resilient means biasing said pawl into engagement with said other flexible lead.

10. In a circuit interrupter, in combination, a fuse tube adapted to be mounted in a substantially vertical position for receiving a fuse link, a housing at the lower end of said fuse tube opening downwardly, and an indicator held in a relatively obscure position within said housing until said fuse link operates, said indicator being adapted to move out of said housing to a position where it can readily be seen on operation of said fuse link.

11. In a circuit interrupter, in combination, a fuse tube adapted to be mounted in a substantially vertical position for receiving a fuse link, a housing at the lower end of said fuse tube opening downwardly, and an indicator pivotally mounted on said housing and held therein in a relatively obscure position by said fuse link and biased downwardly, said indicator being released for downward movement to a position where it is readily visible on operation of said fuse link.

12. In a circuit interrupter, in combination, a fuse tube adapted to be mounted in a substantially vertical position for receiving a fuse link having a flexible lead extending from at least one end thereof, terminal means at the upper end of said fuse tube for receiving the other end of said fuse link, a metallic housing at the lower end of said fuse tube opening downwardly and adapted to receive said flexible lead, and an indicator pivotally mounted on said housing and held therein in a relatively obscure position by said fuse link and biased downwardly, said indicator being released for downward movement to a position where it is readily visible on operation of said fuse link, the biasing action applied to said indicator tensioning said fuse link.

13. In a circuit interrupter, in combination, a fuse tube adapted tobe mounted in a substantially vertical position for receiving a fuse link, a housing at the lower end of said fuse tube opening downwardly, and indicator means including a .distinctively colored reflecting member held thereby in a relatively obscure position within said housing until said fuse link operates, said indicator means being adapted to move said reflecting member out of said housing to a posi-. tion where it can receive and reflect light rays impinging thereon so that the occurrence of a blown fuse link' can be readily detected from a distance.

14. In a circuit interrupter, in combination, a fuse tube adapted to be mounted in a substantially vertical position for receiving a fuse link. a housing at the lower end of said fuse tube opening downwardly, and indicator means including a red glass member held thereby in a relatively obscure position within said housing until said fuse link operates, said indicator means being adapted to move said red glass member out of said housing to a position where it can receive and reflect light rays impinging thereon so that the occurrence of-a blown fuse link can be readily detected from a distance.

HUGH A. 'I'RIPIE'I'I. 

